Commit e7cb3744 authored by Russell Gallop's avatar Russell Gallop
Browse files

[LLD][ELF] Add time-trace to ELF LLD 

This adds some of LLD specific scopes and picks up optimisation scopes
via LTO/ThinLTO. Makes use of TimeProfiler multi-thread support added in
77e6bb3c.

Differential Revision: https://reviews.llvm.org/D71060
parent abe01e17

lld/ELF/Config.h

+2 −0
Original line number Diff line number Diff line
@@ -192,6 +192,7 @@ struct Configuration { 
  bool trace;

  bool thinLTOEmitImportsFiles;

  bool thinLTOIndexOnly;

  bool timeTraceEnabled;

  bool tocOptimize;

  bool undefinedVersion;

  bool useAndroidRelrTags = false;
@@ -243,6 +244,7 @@ struct Configuration { 
  unsigned ltoo;

  unsigned optimize;

  unsigned thinLTOJobs;

  unsigned timeTraceGranularity;

  int32_t splitStackAdjustSize;



  // The following config options do not directly correspond to any

lld/ELF/Driver.cpp

+62 −30
Original line number Diff line number Diff line
@@ -56,6 +56,7 @@ 
#include "llvm/Support/Path.h"

#include "llvm/Support/TarWriter.h"

#include "llvm/Support/TargetSelect.h"

#include "llvm/Support/TimeProfiler.h"

#include "llvm/Support/raw_ostream.h"

#include <cstdlib>

#include <utility>
@@ -487,6 +488,13 @@ void LinkerDriver::main(ArrayRef<const char *> argsArr) { 
  if (args.hasArg(OPT_version))

    return;



  // Initialize time trace profiler.

  if (config->timeTraceEnabled)

    timeTraceProfilerInitialize(config->timeTraceGranularity, config->progName);



  {

    llvm::TimeTraceScope timeScope("ExecuteLinker");



    initLLVM();

    createFiles(args);

    if (errorCount())
@@ -506,21 +514,37 @@ void LinkerDriver::main(ArrayRef<const char *> argsArr) { 
    switch (config->ekind) {

    case ELF32LEKind:

      link<ELF32LE>(args);

    return;

      break;

    case ELF32BEKind:

      link<ELF32BE>(args);

    return;

      break;

    case ELF64LEKind:

      link<ELF64LE>(args);

    return;

      break;

    case ELF64BEKind:

      link<ELF64BE>(args);

    return;

      break;

    default:

      llvm_unreachable("unknown Config->EKind");

    }

  }



  if (config->timeTraceEnabled) {

    // Write the result of the time trace profiler.

    std::string path = args.getLastArgValue(OPT_time_trace_file_eq).str();

    if (path.empty())

      path = (config->outputFile + ".time-trace").str();

    std::error_code ec;

    raw_fd_ostream os(path, ec, sys::fs::OF_Text);

    if (ec) {

      error("cannot open " + path + ": " + ec.message());

      return;

    }

    timeTraceProfilerWrite(os);

    timeTraceProfilerCleanup();

  }

}



static std::string getRpath(opt::InputArgList &args) {

  std::vector<StringRef> v = args::getStrings(args, OPT_rpath);

  return llvm::join(v.begin(), v.end(), ":");
@@ -958,6 +982,9 @@ static void readConfigs(opt::InputArgList &args) { 
      getOldNewOptions(args, OPT_thinlto_object_suffix_replace_eq);

  config->thinLTOPrefixReplace =

      getOldNewOptions(args, OPT_thinlto_prefix_replace_eq);

  config->timeTraceEnabled = args.hasArg(OPT_time_trace);

  config->timeTraceGranularity =

      args::getInteger(args, OPT_time_trace_granularity, 500);

  config->trace = args.hasArg(OPT_trace);

  config->undefined = args::getStrings(args, OPT_undefined);

  config->undefinedVersion =
@@ -1604,6 +1631,7 @@ static Symbol *addUndefined(StringRef name) { 
// Because all bitcode files that the program consists of are passed to

// the compiler at once, it can do a whole-program optimization.

template <class ELFT> void LinkerDriver::compileBitcodeFiles() {

  llvm::TimeTraceScope timeScope("LTO");

  // Compile bitcode files and replace bitcode symbols.

  lto.reset(new BitcodeCompiler);

  for (BitcodeFile *file : bitcodeFiles)
@@ -1733,6 +1761,7 @@ template <class ELFT> static uint32_t getAndFeatures() { 
// Do actual linking. Note that when this function is called,

// all linker scripts have already been parsed.

template <class ELFT> void LinkerDriver::link(opt::InputArgList &args) {

  llvm::TimeTraceScope timeScope("Link", StringRef("LinkerDriver::Link"));

  // If a -hash-style option was not given, set to a default value,

  // which varies depending on the target.

  if (!args.hasArg(OPT_hash_style)) {
@@ -1772,8 +1801,11 @@ template <class ELFT> void LinkerDriver::link(opt::InputArgList &args) { 
  // symbols that we need to the symbol table. This process might

  // add files to the link, via autolinking, these files are always

  // appended to the Files vector.

  {

    llvm::TimeTraceScope timeScope("Parse input files");

    for (size_t i = 0; i < files.size(); ++i)

      parseFile(files[i]);

  }



  // Now that we have every file, we can decide if we will need a

  // dynamic symbol table.

lld/ELF/ICF.cpp

+5 −1
Original line number Diff line number Diff line
@@ -84,6 +84,7 @@ 
#include "llvm/ADT/StringExtras.h"

#include "llvm/BinaryFormat/ELF.h"

#include "llvm/Object/ELF.h"

#include "llvm/Support/TimeProfiler.h"

#include "llvm/Support/xxhash.h"

#include <algorithm>

#include <atomic>
@@ -525,7 +526,10 @@ template <class ELFT> void ICF<ELFT>::run() { 
}



// ICF entry point function.

template <class ELFT> void doIcf() { ICF<ELFT>().run(); }

template <class ELFT> void doIcf() {

  llvm::TimeTraceScope timeScope("ICF");

  ICF<ELFT>().run();

}



template void doIcf<ELF32LE>();

template void doIcf<ELF32BE>();

lld/ELF/LTO.cpp

+3 −0
Original line number Diff line number Diff line
@@ -113,6 +113,9 @@ static lto::Config createConfig() { 


  c.HasWholeProgramVisibility = config->ltoWholeProgramVisibility;



  c.TimeTraceEnabled = config->timeTraceEnabled;

  c.TimeTraceGranularity = config->timeTraceGranularity;



  c.CSIRProfile = std::string(config->ltoCSProfileFile);

  c.RunCSIRInstr = config->ltoCSProfileGenerate;

lld/ELF/MarkLive.cpp

+2 −0
Original line number Diff line number Diff line
@@ -31,6 +31,7 @@ 
#include "lld/Common/Strings.h"

#include "llvm/ADT/STLExtras.h"

#include "llvm/Object/ELF.h"

#include "llvm/Support/TimeProfiler.h"

#include <functional>

#include <vector>
@@ -323,6 +324,7 @@ template <class ELFT> void MarkLive<ELFT>::moveToMain() { 
// input sections. This function make some or all of them on

// so that they are emitted to the output file.

template <class ELFT> void markLive() {

  llvm::TimeTraceScope timeScope("markLive");

  // If -gc-sections is not given, no sections are removed.

  if (!config->gcSections) {

    for (InputSectionBase *sec : inputSections)